package com.langxin.erp.util.security;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import org.apache.log4j.Logger;

/**
 * MD5加密解密
 * @author gu
 *
 */
public class MD5Util {

	private static Logger log = Logger.getLogger(MD5Util.class);
	
	private final static char[] strDigits = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
	
	public static String encode(String s){
		try {
			byte[] btInput = s.getBytes();
			// 获得MD5摘要算法的 MessageDigest 对象
			MessageDigest mdInst = MessageDigest.getInstance("MD5");
			// 使用指定的字节更新摘要
			mdInst.update(btInput);
			// 获得密文
			byte[] md = mdInst.digest();
			// 把密文转换成十六进制的字符串形式
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
			    byte byte0 = md[i];
			    str[k++] = strDigits[byte0 >>> 4 & 0xf];
			    str[k++] = strDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (NoSuchAlgorithmException e) {
			log.error("MD5 encode error,reason is " + e.getMessage());
			return null;
		}
	}
	
	public static void main(String[] args) {
		System.out.println(encode("111111"));
	}
}
